Patent · US Expired

Method of separating and purifying cations by ion exchange with regenerable porous glass

US4687581A · kind A · utility

13Cited by
12References
38Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 30, 1984
Grant dateAug 18, 1987
Priority date
Expiry dateJan 30, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03C2201/50
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method for separating and purifying cations by ion exchange with regenerable porous glass. More specifically, the method is for decontaminating toxic waste streams such as a radioactive waste streams and concentrating the radioactive cations contained therein which comprises passage of the waste stream through an ion exchange medium of porous silicate glass or silica gel. In one embodiment, a liquid nuclear waste stream is passed through an ion exchange column containing porous silicate glass or silica gel having a plurality of .tbd.Si--O--Z groups wherein Z represents a non-radioactive cation (hydrogen, alkali metals, Group Ib metals and ammonium cations, and mixtures thereof) to displace the non-radioactive cations of the silicate glass or silica gel by the radioactive cations of the waste stream. Thereafter, the ion exchange medium is contacted with an aqueous solution of an acid to strip the radioactive cations therefrom and the stripped ion exchange medium is regenerated. The stripped ion exchange medium can be regenerated by contacting it with an aqueous basic solution of an alkali metal or ammonium ion. Additional liquid radioactive waste is contacted with the regenerated …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.